Fungal Root Rot

What Is Fungal Root Rot?

Fungal root rot is exactly what it sounds like - a disease that attacks the roots of trees and plants, caused by non-beneficial fungal spores living in the soil. It thrives in wet, poorly drained conditions, which we see a lot here in Central Texas after heavy rains or in compacted soil.

Once it sets in, it can slowly kill a tree from the underground up, long before most people even know there’s a problem.

Common Types of Fungal Root Rot

There are a few different fungi responsible for root rot. Some go after trees, others hit flowers or vegetables. Here's a quick breakdown:

• Phytophthora – The most common one, affects a wide range of plants and trees
• Pythium – Hits seedlings and young plants
• Rhizoctonia – Shows up in gardens, targets ornamentals and veggies
• Fusarium – Mostly found in ornamental plant roots
• Thielaviopsis – Affects grasses and ornamental plants

If you have any kind of root decay or yellowing leaves, this could be the reason.

Symptoms to Look Out For

Here’s what we see most often when a tree is dealing with root rot:

• Wilting in the canopy (even if you’re watering)
• Yellowing or browning leaves
• Roots that smell bad or feel soft and spongy
• Visible reduction in root mass
• Brown or black roots (see image below)
• In severe cases — tree death

If your tree is wilting and you're doing everything "right," it might be time to look below the surface.

Signs of Disease

• Fungal conks (mushroom-like growths) forming near the root collar
• White fungal threads or growth along the fibrous roots
• In some cases, the tree may look okay above ground — but the root system is already compromised

Want to be 100% sure? We can send in lab samples from the roots to confirm if fungal root rot is the cause.

How to Prevent Root Rot

There’s no magic spray that reverses root rot once it sets in. The key is prevention by creating conditions where fungi can’t take over in the first place.

✅ Tips to Reduce Root Rot Risk:

• Avoid overwatering (let soil dry between watering)
• Improve drainage around your trees
• Build healthy soil with compost and mulch under the drip line
• Deep root injections can break up compacted soil and help improve aeration
• Air spading (special equipment we use) mixes and aerates soil around the roots
• Use preventative fungicides before you see symptoms

Once root rot hits, it’s about managing the damage, not curing the tree. Prevention is everything.

How Tree Scouts Can Help

Our certified arborists have seen this problem more times than we can count, especially in neighborhoods with heavy clay or compacted soil.

• We can inspect your trees, look for signs of fungal root rot, and take soil samples if needed
• If we find early-stage issues, we’ll recommend next steps that actually make a difference
• If the tree can’t be saved, we’ll walk you through safe removal and how to rebuild the soil for future planting

Our team has the scientific know-how to help diagnose fungal root rot. If its there then we can help you deal with the aftermath of the disease.

🌿 Book a Free Tree Health Assessment

Think your tree might be in trouble? Or just want to get ahead of a potential problem?

📞 Call or text us today at 512-265-0861
🌐 Or book online at treescouts.com/contact

Healthy roots = happy trees. Scout’s honor. 🌳